Results Show Progress in Bank's Efforts to Shrink Units That Don't Fit Its Strategy

Citigroup Inc. reported a surge in second-quarter profit from a strong securities business, but executives warned that a slowdown in emerging markets could weigh on the company's results later this year.

The third-largest U.S. bank by assets said Monday that net income rose to $4.18 billion, or $1.34 a share, a 42% jump from a year earlier. Subtracting an accounting gain left Citigroup with $1.25 a share, beating analysts' consensus...